The aim of this paper is to explore from a historiographical perspective the complex trajectories of nationalism in the complex and difficult neighbourhood that is the Horn of Africa. I will argue that while recent conflicts have elements of specificity related to regional and international politics, important elements of understanding can be recovered through a broader retrospective look that assesses the ways in which social, economic and cultural interactions have shaped regional politics. A central element underpinning my analysis is a strong conviction that contemporary crises must also be analysed from a regional perspective in order to escape the trap of reading political processes exclusively through the lens of the nation-state. States are crucial actors that cannot be ignored, but they do not live in a vacuum; on the contrary, they are often interdependent.